The receptionists were lovely and the location on the beach (though S'arenal is a godawful neighbourhood) is also convenient.
every room has a balcony, yes, but you may be facing the council estate looking building next door. however, at least it overlooks a little rock garden so the air feels fresh and it feels private.
My only issue was the bathroom, from which we deduced the smell of mold/mildew was coming. However, everything seemed clean, so I expect, the cleaning was either superficial or that there needs to be a review of the plumbing and draining systems.
the smell was pretty bad when we came back from a day of sight seeing and also when we first entered the room, but opening the windows cleared it out (temporarily) within half an hour or so.
As for the rest it was generally clean (not under the cupboards) and well-presented. The rooms were rather large, i think, though bare. . . for the price i can't fault it. It was very very cheap.
The location, surrounded as it is by German pubs, ugly buildings, and tacky tourist things, lacks all character, is not convenient to the center (last "fast" bus (30mins to Pl. Espanya) stops running at 21:30 and the last "slow" bus (40 mins to Pl. Espanya) stops around 01.00).
I will say that while the cycle into Palma is not so lovely after kilometre #5, the bicycle path into Palma is amazing and very very very well done. As advice, I would suggest paying a bit extra to stay in Palma though because there is nothing to do in S'Arenal but sit on the beach and go to biergartens or eat overpriced food and you can do that in other parts of the country while being more conveniently located to see the rest of the island.